/Engine/Source/Runtime/Engine/Classes/Particles/Spawn/ParticleModuleSpawn.h
Retrieve the spawn amount this module is contributing. Note that if multiple Spawn-specific modules are present, if any one of them ignores the SpawnRate processing it will be ignored.
bool false if the SpawnRate should be ignored. true if the SpawnRate should still be processed.
virtual bool GetSpawnAmount ( [FParticleEmitterInstance](API\Runtime\Engine\FParticleEmitterInstance) * Owner, int32 Offset, float OldLeftover, float DeltaTime, int32 & Number, float & Rate )